Proxy Mobile IPv6 (Pmip6) Protocol is a mobility management protocol based on network which liberates mobile nodes (MNs) from the mobility management protocol. In a Pmip6 protocol architecture, since the mobility management protocol is not supported by the mobile nodes and the mobile nodes are not capable of directly participating in signaling interactions, i.e. messages may not be directly transmitted to a correspondent node (CN) during message transmission, a Proxy Mobile Agent (PMA) is therefore provided to substitute for the mobile nodes to accomplish relevant interactions of protocol signaling and to transmit/receive messages. That is, the PMA simulates home links and announces home prefixes which may give the mobile nodes a false feeling of always being on the home links. The PMA is also called the Mobile Access Gateway (MGW).
In the recent Pmip6 protocol architecture, the procedure for receiving and responding a message by a mobile node is described below. Referring to FIG. 1, a schematic of a message interaction between a correspondent node and a mobile node in the PMIP architecture of conventional art is illustrated.
First, the correspondent node sends a message to a home address of the mobile node. A home agent captures the message, queries for a binding list based on the home address to obtain a PMA address of the mobile node, and sends the message to the PMA of the mobile node through a tunnel between the home agent and the PMA of the mobile node. And then, the PMA of the mobile node directly sends the message to the mobile node based on the home address of the mobile node.
Next, upon receipt of the message from the correspondent node, the mobile node directly replies a message to the correspondent node with the home address being a source address. The PMA captures the message and sends the message to the home agent through the tunnel between the home agent and the PMA of the mobile node. The home agent strips off an outer IP message header and sends the inner message to the correspondent node.
It is noted from the above interaction of message, because the mobile management protocol is not supported by the mobile node in PMIP6 and the message can not be directly sent to the correspondent node, the home agent is therefore provided to operate the message interaction between the mobile node and the correspondent node, which reduces the communication efficiency and the routing performance.